The courtroom setting is often assumed to be stressful for children who testify, potentially leading to secondary victimization and long-term mental health problems. However, research on the impact of testifying is mixed, with some studies finding negative effects while others find no impact or even a restorative effect. This discrepancy may be due to the specific conditions under which children testify. The new European Judicial Policy emphasizes child-friendly justice, adapted to the needs of young individuals. Spain has implemented measures to improve the court experience for children, including recording statements (preconstituted evidence) in specially designed child-friendly rooms. This study investigates whether stress levels remain high or reach harmful levels in a child-friendly court setting, using real-time stress monitoring.

Existing literature shows conflicting findings on the effects of testifying on children. While some studies report high levels of stress and negative consequences, others demonstrate no adverse effects or even potential restorative outcomes. This disparity can be attributed to the court setting and procedures. The Council of Europe's Guidelines on child-friendly justice emphasize the importance of a supportive environment and procedures. Previous research using simulated trials and heart rate variability (HRV) suggests that courtroom settings are more stressful than other environments. The use of child-friendly facilities and video recording of testimony is increasingly encouraged to mitigate stress.

This field study used a simple repeated-measures design with 42 Spanish minors (73.8% girls, mean age 12.5 years) who testified as victims of violence in a specialized child-friendly court. Stress was measured in real-time using a HUAWEI Band 6 smart band, assessing heart rate variability (HRV). State and trait anxiety were assessed using the Spanish version of Spielberger's State-Trait Anxiety Inventory for Children (STAIC) for those under 15 and the STAI for those 16 and over. Measurements were taken at three occasions: in the waiting room (T1), in the Gesell room during the interview (T2), and in the decompression room after the interview (T3-T7). Data were analyzed using descriptive statistics, independent samples t-tests, and repeated measures ANOVA.

The mean percentile of anxiety remained at moderate levels, while stress remained at medium-low levels. No significant differences in anxiety or stress were found based on gender or type of crime. Repeated measures ANOVA revealed a significant effect of the court setting on stress levels (F(2) = 9.91, p < 0.001, η²=0.195). Post-hoc analysis with Bonferroni adjustment showed significantly higher stress in the Gesell room compared to the decompression room. There was no significant difference between stress in the waiting room and the Gesell room. Three children experienced high stress, exclusively in the Gesell room during testimony. Correlation analysis showed significant positive associations between stress and anxiety scores in the waiting room, but not during the Gesell room interview or the post-interview period. The smart band demonstrated test-retest reliability and discriminant validity in assessing stress.

The findings indicate that while testifying in a child-friendly court may cause some stress, levels generally remained within a medium-low range and did not reach levels considered detrimental to children's health. The highest stress was reported in the Gesell room during the testimony, possibly due to the emotional nature of recalling traumatic events. The stress levels observed are less than those reported in studies conducted in non-child-friendly courts. The significant difference in stress levels between the Gesell room and the decompression room may reflect a stress-release effect after the stressful experience of recounting the events. The lack of correlation between stress and anxiety scores beyond the waiting room could be explained by the Multidimensional Anxiety and Coping Theory, which suggests a difference between state anxiety and acute stress responses to specific events.

This study demonstrates that the child-friendly court environment, while not eliminating stress entirely, mitigates acute stress levels during children's testimony to non-harmful levels. These results support the implementation of child-friendly justice systems. Future research should include larger samples, compare child-friendly and non-child-friendly courts, and address the limitations of self-reported anxiety measures in this context.

The study's limitations include the relatively small sample size, the convenience sampling method, lack of a control group, focus solely on acute stress, and potential influence of participants' knowledge of the research objectives on self-reported anxiety. The use of only one type of anxiety questionnaire for different age groups may have also influenced the results. The absence of a distress scale to directly compare physiological and psychological distress is also a limitation.